Apparatus for automatically opening closed circuits



(No Model.) 2 Sheets-Sheet 1.

J. P. TIRRELL.

APPARATUS FOR AUTOMATICALLY OPENING CLOSED CIRCUITS- No. 304,376.Patented Sept. 2, 1884.

n. wzrzn s. Pnam-mm m. WalhingOlL n. c. \r

(No Model.) 2 Sheets-Sheet 2 J. P. TIRRELL.

APPARATU$ FOR AUTOMATICALLY OPENING CLOSED CIRCUITS- Patented Sept. 2,1884.

w M M I Wain/asses.

N Finis, mmumo' n m, Wzxhinglmu no,

,NITE STATES JAooB P. TIRRELL, or BOSTON, ASSIGNOR TO GEORGE r. PINKHAM,OF

oUrNoY, MASSACHUSETTS.

APPARATUS FOR AUTOMATICALLY OPENING CLOSED CIRCUITS.

QPECIPICAT ION forming part of Letters Patent No. 304,376, datedSeptember 2, 1884.

Application filed December 1, was. (No mo'deLl ToaZZ whont it mayconcern.-

-Be it known that I, JACOB'P. TIRRELL, of

Boston, in the county of Suffolk and State of ment of a circuit causinga ground-connection at a gasburner is prevented from weakening thebattery or injuriously affecting the other branch circuits in a systemhaving a series of branch circuits, each including a gas-burner.

The invention consists, as a whole, in the combination of an electriccircuit having one or more branch circuits, each provided with anelectro-niagnet and with suitable gas-lighting devices, a spark-coil'orits equivalent-in said circuit provided with one or more armatures,switching devices, substantially as described, adapted to cut out abranch circuit when said armatures are fully attracted, and a mechanicalresistance or retarding device, whereby the armature 'or armatures ofthe spark-coil are prevented from being fully attracted by a momentaryclosure of the circuit.

In the accompanying drawings, Figure l is a top view of my improvedapparatus. Fig. 2 is an elevation as viewed from the lower side of Fig.1, and with parts broken away. Fig. 3 is an elevation from the right ofFig. 1. Figs. 4 and 5 are detached. views of parts of the apparatus.Fig. 6 is a diagram of connections.

In; these views, A is the wooden base, while B,Fig. 2, is aprotecting-cover for the apparatus.

O is the usual spark-coil secured to base A, and provided with a core,c, of iron wires. (Indicated by dotted lines in Fig. 1.)

Uprights D, Figs. 1, 2, 3, secured to base A, support rock-shafts d,pivoted therein, and carrying armaturesd, which are arranged to beattractedby the core 0 of coil 0. Levers a a, secured to rock-shafts cl,are connected at a by a pin and slot, as shown, so as to movesimultaneously. Lever'a has a pistonq'od, e, se cured to its free'lend,and said rod is-fiired to a piston, e, (see sectional view, Fig 4,)which moves loosely in a vessel, E, filled with oil or 7 similar fluid,thewhole forming afdash- 'pot or mechanical resistance, and renderingthe movement of levers a a, gradual. I do not limit myself, however, tothis form of mechanical resistance, as any other suitable devices whichwill similarly retard the movement of the levers a a may be used withoutdeparting from the spirit of my invention; nor do I limit myself to theprovision of two armatures for the spark-coil, as a single armatureanaybe employed, if preferred.

Secured to base A are a number of electromagnets, F, one being placed ineach of the circuits branching from the spark-coil, and arranged tooperate armaturrs f, mounted on springs f, which latter aresecuredtoaconr mon support, f fastened to base Al r A rock-shaft, G,pivoted in bearings G, supported by a standard, G carries a metallicstrip formed into contact-arms g, which project obliquely downwardtoward armatures f. Vertical contact-springs g, secured to the free endsof armatures f, are arranged to normally make yielding contact withcontact-arms g,

as shown by full lines in Figs. 1 and 2, and by dotted lines in Figs. '3and 5, thereby completing the circuits which pass through said arms andsprings. This arrangement of circuits is shown in Fig. 6,which shows asingle circuit consisting of battery H, wire 1, sparkcoil 0, wire 2,shaft G, contact-arm 5/, spring 9, armature f, and spring f,'wire 3;magn'et F,wire 4, gasburner I, and wire 5, to'battery. The Springs 9 andcontact-arms g constitute switching devices, whereby the branch circuitsare automatically opened after a prolonged closure, as hereinafterdescribed. Of course, this circuit is normally broken at the gas-burner,and only closed by the contact of the electrodes at the burner duringthe operation of lighting.

It is obvious that one or any greater number of circuits may be run fromthe battery and spark-coil, each requiring an electro-magnet F andcorresponding parts.

A two-armed lever, K, is secured to the end of the shaft G, and has itsplay limited'by two pins, 7.4 between which its lower arm, 7c,vibrates,while its horizontal arm hasit's'free end bent at a right angleand arranged to be engaged by an arm, Z, secured to arm a; consequently,whenever armatures d are operated, as described, arm Z rises, engagesarm k of lever K, which is normally depressed by gravity, and raises thesame as far aspins k al low, as shown in full lines in Fig. 8.

The operation of the apparatus would be as follows: A closure of circuitin any one a branch would first attract armature f in that branch,andthus draw contact-spring 9 downward, but not far enough to release itfrom contact-arm g, as it would merely rub along it without breaking theconnection, and, in fact, this would be liable to occur every time thecircuit was closed for lighting purposes; but if the closure of circuitbe permanent, owing to derangement, armature f in the affected circuitbeing drawn downward, armatures d will slowly act to raise levers a aand arm Z, and at or near the end of the upward movement of said arm itwill engage the arm k of the lever K, and thus simultaneously raise allof the contact-arms g on shaft Ghigh enough to disengage thecontact-spring g 011 the armature f, which is depressed,as hereinbeforedescribed, from the corresponding contact arm, when resiliency of saidcontactspring will cause it to spring inward toward shaft G, as shown infull lines in Fig. 5, out of contact with its contact-arm g. This willoccur only in the case of the particular spring which we haveconsidered,for all of the otherarmatures f not being depressed, thesprings g thereon will not be disengaged from their contact-arms g, asboth the depression of said springs and the raising of said contact-armsis required for disengagement. The circuit being now broken in thederanged branch, and neither armatures f nor d being then attracted, thelevers a a. will fall by gravity and the apparatus resume its normalposition, leaving the deranged circuit cut out, and with thecontactspring 9 in that circuit out of contact with its correspondingcontact-arm, To restorethe springs y to their normal position afterafault had been remedied, I provide a rock-shaft, M, provided with armsm, corresponding to those of shaft G, and with a lever, m, so arrangedthat by gravity said arms at will normally rest, as shown in Fig. 5 infull lines; but the depres sion of the lever m will cause said arms m toengage contact-springs g and move them into the position shown in dottedlines in Fig. 5. The downward movement of lever m is limited by abracket, m secured to support as shown. As a convenient means ofoperating said lever and rock-shaft, I provide a push-knob, N, Fig. 2,sliding through the cover 13 of the apparatus, and normally raised by aretractile spring, a, the depression of said button bringing its lowerend against the extremity of lever m and forcing it downward. Topartially counterbalance the excess of weight of levers a a, I provide aweight, b, Figs. land 2, secured to an arm, I), by a screw, Z), passingthrough a slot in the same, so as to allow said weight being adjusted toregulate the time or rate of operation of the shaft d, to which said armis attached. The employment of dashpot or mechanical resistance Erenders armatures d practically inoperative under the ordinary lightingcondition; but the attraction caused by the permanent closure ofcircuit, which is liable to be produced by derangement of the apparatusattached to the burner, will cause the affected circuit to be cut outafter the lapse of half a minute, more or less.

It is evident that a separate electro-magnet may be used to operatelevers a a; but the spark-coil arranged as shown is more convenient andeconomical.

The described apparatus will usually be located in some convenient partof a building having an electric gas-lighting, system and automaticallycut out the branch circuit of 8 any burner or burners in the system incase of an accidental ground-connection caused by the derangement of theterminal or contact points or otherwise. By thus cutting out anyderanged branch circuit, waste of batterypower is prevented, and theoperation of the circuits at the other burners is unimpaired. Failure ofthe lighting apparatus to operate at any burner gives notice that thecircuit at that burner is disarranged, and has been cut out by theimproved apparatus, so that an electrician may be summoned, who, aftermaking the necessary repairs, will reset the apparatus by depressing thepush-knob, as above described.

I claim 1. The combination of an electric circuit having one or morebranch circuits, each provided with an electro-magnet and with suitablegas-lighting devices, a spark-coil or its equivalent in said circuit,provided with one or more armatures, switching devices, substantially asdescribed, adapted to cut out a branch circuit when said armatures arefully attracted, and a mechanical resistance or retarding device,whereby the armature or armatures of the spark-coil are prevented frombeing fully attracted by a momentary closure of the circuit, as setforth.

2. An electric circuit having a gas-lighting device, an electro-magnetprovided with an armature, and a spark-coil or its specified equivalent,also having an armature combined with switching devices, substantiallyas described, which are caused to cut out the gaslighting devices by thecomplete attraction of both of said armatures when a prolonged closureof the circuit occurs, and a mechanical resistance or retarding device,whereby a momentary or brief closure of the circuit caused by theordinary contact of the electrodes of the gas-1i ghting device isprevented from completely attracting both armatures and operating theswitching devices, as set forth.

3. The combination of an electric circuit having a series of branchcircuits, each including gas-lighting devices, and an clectro'mag nethaving an armature, a spark-coil or its equivalent in said circuit, alsohaving an armature, a mechanical resistance,whereby the movement of saidarmatures is rendered gradual and insensitive to momentary closings ofthe circuit, and switching devices for the branch circuits, eachoperated by the simultaneous action of the electromagnet or branch towhich it belongs, and the retarded armature or armatures, whereby anybranch is automatically cut out from the main circuit in case ofderangement, as set forth.

4. The combination of an electric circuit having two or more branchcircuits, each including gas-lighting devices, an electro-magnet and anarmature therefor, a spark-coil or its equivalent located in saidcircuit, and having an armature, levers operated by said armatures, amechanical resistance or dash-pot, whereby the rate of movement of saidarmatures when attracted by the spark-coil is limited, and Switchingdevices for said branch circuit, composed of a series of contact-armsadapted to be operated simultaneously by said levers, and acorresponding series of contactsprings on the armatures of the magnetsin the branch circuits, and operated independently thereby, said contactsprings and arms being normally in yielding contact, and dis connectedonly by the movement of said levers caused by a prolonged closure of thecircuit, as set forth.

5. In an electric gas-lighting apparatus, the combination, with thearmatures of the switchmagnets, provided with the spring-arms g, of therock-shaft having contact-arms g, and means, substantially as described,for restoring said arms to their normal position.

6. The combination of the spark-coil G, or its equivalent, the armaturescl d thereof, the

levers a a, secured to said armatures, and having a jointed connectionto each other, the mechanical resistance or retarding device applied tosaid levers, the branch circuits, including the electro-ma-gnets F,having armaturesf, the switching devices composed of the springs g onarmatures f, and the contactarms 9, secured to a common rock-shaft, G,and means whereby said contact-arms are raised simultaneously byacomplete attraction of the armatures d d, as set forth.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, this 26th day of October, 1883.

J AOOB P. TIRRELL.

lVitnesses:

O. F. BROWN, A. L. WHITE.

